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31.
An Assessment of Stakeholder Perceptions and Management of Noxious Alien Plants in Spain 总被引:1,自引:1,他引:0
Despite biological invasions being a worldwide phenomenon causing significant ecological, economic, and human welfare impacts,
there is limited understanding regarding how environmental managers perceive the problem and subsequently manage alien species.
Spanish environmental managers were surveyed using questionnaires to (1) analyze the extent to which they perceive plant invasions
as a problem; (2) identify the status, occurrence, and impacts of noxious alien plant species; (3) assess current effort and
expenditure targeting alien plant management; and, finally, (4) identify the criteria they use to set priorities for management.
In comparison to other environmental concerns, plant invasions are perceived as only moderately problematic and mechanical
control is the most valued and frequently used strategy to cope with plant invasions in Spain. Based on 70 questionnaires
received, 193 species are considered noxious, 109 of which have been the subject of management activities. More than 90% of
species are found in at least one protected area. According to respondents, the most frequently managed species are the most
widespread across administrative regions and the ones perceived as causing the highest impacts. The perception of impact seems
to be independent of their invasion status, since only half of the species identified as noxious are believed to be invasive
in Spain, while 43% of species thought to only be casual aliens are causing a high impact. Records of management costs are
poor and the few data indicate that the total actual expenditure amounted to 50,492,437 € in the last decade. The majority
of respondents stated that management measures are insufficient to control alien plants due to limited economic resources,
lack of public awareness and support, and an absence of coordination among different public administrations. Managers also
expressed their concern about the fact that much scientific research is concerned with the ecology of alien plants rather
than with specific cost-efficient strategies to manage alien species. 相似文献
32.
33.
Schaefer CE do Amaral EF de Mendonça BA Oliveira H Lani JL Costa LM Fernandes Filho EI 《Environmental monitoring and assessment》2008,140(1-3):279-289
The relationships between soils attributes, soil carbon stocks and vegetation carbon stocks are poorly know in Amazonia, even
at regional scale. In this paper, we used the large and reliable soil database from Western Amazonia obtained from the RADAMBRASIL
project and recent estimates of vegetation biomass to investigate some environmental relationships, quantifying C stocks of
intact ecosystem in Western Amazonia. The results allowed separating the western Amazonia into 6 sectors, called pedo-zones:
Roraima, Rio Negro Basin, Tertiary Plateaux of the Amazon, Javari-Juruá-Purus lowland, Acre Basin and Rondonia uplands. The
highest C stock for the whole soil is observed in the Acre and in the Rio Negro sectors. In the former, this is due to the
high nutrient status and high clay activity, whereas in the latter, it is attributed to a downward carbon movement attributed
to widespread podzolization and arenization, forming spodic horizons. The youthful nature of shallow soils of the Javari-Juruá-Purus
lowlands, associated with high Al, results in a high phytomass C/soil C ratio. A similar trend was observed for the shallow
soils from the Roraima and Rondonia highlands. A consistent east–west decline in biomass carbon in the Rio Negro Basin sector
is associated with increasing rainfall and higher sand amounts. It is related to lesser C protection and greater C loss of
sandy soils, subjected to active chemical leaching and widespread podzolization. Also, these soils possess lower cation exchangeable
capacity and lower water retention capacity. Zones where deeply weathered Latosols dominate have a overall pattern of high
C sequestration, and greater than the shallower soils from the upper Amazon, west of Madeira and Negro rivers. This was attributed
to deeper incorporation of carbon in these clayey and highly pedo-bioturbated soils. The results highlight the urgent need
for refining soil data at an appropriate scale for C stocks calculations purposes in Amazonia. There is a risk of misinterpreting
C stocks in Amazonia when such great pedological variability is not taken into account. 相似文献
34.
Pesch R Pehlke H Jerosch K Schröder W Schlüter M 《Environmental monitoring and assessment》2008,136(1-3):313-325
In this article a concept is described in order to predict and map the occurrence of benthic communities within and near the
German Exclusive Economic Zone (EEZ) of the North Sea. The approach consists of two work steps: (1) geostatistical analysis
of abiotic measurement data and (2) calculation of benthic provinces by means of Classification and Regression Trees (CART)
and GIS-techniques. From bottom water measurements on salinity, temperature, silicate and nutrients as well as from punctual
data on grain size ranges (0–20, 20–63, 63–2,000 μ) raster maps were calculated by use of geostatistical methods. At first
the autocorrelation structure was examined and modelled with help of variogram analysis. The resulting variogram models were
then used to calculate raster maps by applying ordinary kriging procedures. After intersecting these raster maps with punctual
data on eight benthic communities a decision tree was derived to predict the occurrence of these communities within the study
area. Since such a CART tree corresponds to a hierarchically ordered set of decision rules it was applied to the geostatistically
estimated raster data to predict benthic habitats within and near the EEZ. 相似文献
35.
Western China has lagged a lot in terms of industrial structure and economic development,compared with the national average.And China announced its target of CO_2 emission reduction,i.e.by 2020,CO_2 emission per GDP will drop by40-45%compared with 2005.The target will be incorporated into China's long-term industrial planning.Against this background,this paper will make a comprehensive examination of the industrial development of Western China,aiming to discover a green and compatible way.First,we analyze the spatiotemporal evolution of regional industrial structure for the period 2000-2010.Second,we try to discover the industrial structure optimization path for Western China by employing the Vector Auto Regression model.Lastly,we try to provide some advice and suggestions for further industrial development in Western China.Our examination shows that further industrial development in Western China should pay full attention to resource conservation and recycling,and develop on a green and compatible path. 相似文献
36.
Tayeb Wafa Koubaa Nadia Nakbi Amel Chaieb Ikbal Tayeb Insaf Kassab Asma 《Journal of environmental science and health. Part. B》2013,48(12):1058-1069
In this study, a cohort of farmers from the Mateur region in the North of Tunisia, were interviewed and examined for the biochemical effects of pesticides. We studied their haematological profile, lipid parameters, serum markers of nephrotoxicity and hepatotoxicity. We also evaluated the activities of Butyrylcholinesterase (BChE), Acetylcholinesterase (AChE) and thiolactonase-paroxonase (PON). Moreover, lipid peroxidation and activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) were determined. The duration of pesticide use and the farmers’ age were considered in the analysis. Our results revealed significant differences in some haematological parameters, in liver and kidney functions, in the lipidic status of the pesticide-exposed group. We also reported an increase in the index of incidence of cardiovascular risk in farmer populations. A significant decrease in AChE, BChE and PON levels was found among farmers. Lipid peroxidation, however, increased. The activities of SOD and CAT were remarkably elevated in farmer populations. There was a significant relation between changes in biological markers, the duration of pesticide use and the farmers’ age. This study indicates that a long-term exposure to pesticides may play an important role in the development of vascular diseases via metabolic disorders of lipoproteins, lipid peroxidation and oxidative stress, inhibition of BChE and decrease in thiolactonase-PON levels. 相似文献
37.
38.
Marine Elbakidze Per Angelstam Nikolay Sobolev Erik Degerman Kjell Andersson Robert Axelsson Olle Höjer Sandra Wennberg 《Ambio》2013,42(2):201-214
Protected area (PA) is an indicator linked to policies on ecological sustainability. We analyzed area, size, and categories of PAs in the European boreal forest biome in Norway, Sweden, Finland, and Russia from 1900 to 2010. The PA increased from 1.5 × 103 ha in 1909 to 2.3 × 107 ha in 2010. While the total PA in the boreal biome was 10.8 %, the figures ranged from 17.2 % in the northern, 7.9 % of the middle, and 8.7 % of the southern boreal sub-regions. The median size of PAs varied from 10 to 124 ha among countries. The categories of less strictly PAs increased over time. The proportion of area occupied by PAs is an important response indicator for conservation efforts. However, the use of PA as an indicator of ecological sustainability needs to consider ecosystem representation, functional connectivity and management categories. 相似文献
39.
One would hypothesize that the Common Fisheries Policy, as the umbrella framework for fisheries management in the EU would have the greatest impact on fishers’ communities across Europe. There are, however, biological, economic, social, and political factors, which vary among fishing communities that can affect how these communities react to changes. This paper explores the links between institutional arrangements and ecological dynamics in two European inshore fisheries socio-ecological systems, using a resilience framework. The Mediterranean small-scale fishers do not seem to have been particularly affected by the Common Fisheries Policy regulations but appear affected by competition with the politically strong recreational fishers and the invasion of the rabbit fish population. The inshore fishers along the East coast of Scotland believe that their interests are not as sufficiently protected as the interests of their offshore counterpart. Decisions and initiatives at global, EU, and sometimes national level, tend to take into account those fisheries sectors which have a national economic importance. A socio-ecological analysis can shift the focus from biological and economic aspects to more sustainable long-term delivery of environmental benefits linked to human wellbeing. 相似文献
40.
Flagships are one conservation education tool. We present a proposed flagship species fleet for environmental education in central Chile. Our methods followed recent flagship guidelines. We present our selection process and a detailed justification for the fleet of flagship species that we selected. Our results are a list of eight flagship species forming a flagship fleet, including two small- and medium-sized mammals, the degu (Octodon degus) and the culpeo fox (Lycalopex culpeaus), two birds, the turca (Pteroptochos megapoidius) and the burrowing owl (Athene cunicularia), the Chilean iguana (Calopistes palluma), the tarantula (Grammostola mollicoma), and two trees, the litre (Lithrea caustica) and the espino (Acacia caven). We then describe how these flagships can be deployed most effectively, describing their audience, effective narrative frames, and modes of presentation. We conclude that general selection rules paired with social science background data allow for an efficient selection process. 相似文献